ATL: LAURA - Post-Tropical - Discussion

[Blown Away]

Seems TD13 is moving faster than the NHC track and on the right side of the cone. I would think that would cause the track to shift R due to changing the “angle of ascent”.

[USTropics]

Here are 3 days of 500mb vorticity (from when 98L was a strung out mess of a monsoonal trough to now). You can see how the eastern vort maximum rotated northwest, and once it reached the northern flank of the wave axis, development finally occurred.

[Jr0d]

Right now I do not see anything that will allow the storm to turn north before Florida, that door appears to be shut. Even going north of Lake Okeechobee seems unlikely given the information available to me.

Maybe tomorrow will give some hope with better data for the computer models and a fresh set of eyes for me.

I will likely be raising my Key West storm threat to medium when I wake up tomorrow afternoon, just took some Benadryl so I will be getting much needed sleep soon.

[SFLcane]

Seems TD13 is moving faster than the NHC track and on the right side of the cone. I would think that would cause the track to shift R due to changing the “angle of ascent”.

TCVN all the way now into the straits.

[SFLcane]

TD 13 looks horrible this morning.

[Shell Mound]

TD 13 looks horrible this morning.

Are we looking at the same storm? I see a well-organised system that has improved markedly, both structurally and convectively, since yesterday. In fact, the low-level centre appears to have tightened somewhat, and new convective towers are forming in the immediate vicinity, based on the latest IR frames. Given current trends, TD Thirteen will almost certainly become a tropical storm tonight. (Incidentally, 97L also looks to be slowly but steadily organising and is entering a much more conducive environment today.) One worrisome indication is that outflow is already well established in all quadrants except the northeast, where some lingering, enhanced VWS is resulting in a slight structural tilt, although this inhibitor is quickly diminishing. Structurally, this has all the looks of a potentially powerful hurricane in two to three days. Once an inner core becomes firmly established, this will almost certainly intensify much faster than most of the models are indicating, given its position relative to the TUTT, which should promote efficient “heat sinking.”

[Shell Mound]

While stronger storms moving poleward is generally true, the synoptic set up is more important. Andrew, Irma, and Katrina all took a WSW job before hitting Florida. Andrew and Irma did this as major hurricanes. The assumption that a stronger storm track further north is false.

Based on the upcoming synoptic setup, the ridge doesn’t look to be sufficiently strong and expansive to drive a strong hurricane into South Florida. That’s the “rub.”

At least that’s my preliminary take. I give TD Ten a 60/40 chance to miss South FL to the east. Models will need to show a much stronger ridge for a MH hit on S FL.

Right now the “miss” option has a slight but notable edge over the “hit” option. But I definitely expect TD Ten to become a powerful hurricane in three to five days.

[GCANE]

GFS is forecasting this running thru a long period of PV Streamer interaction from the TUTT.
May have a hard time until it gets into the Bahamas.

[USTropics]

You can see as the convection pulsed and the vorticity became more focused on the northern axis last night, some dry air was/is currently being entrained. Inflow channel is trying to reach down towards South America. That should give it a boost if it can make the connection:

[northjaxpro]

06Z GFS , if it verifies, looks very ominous to darn frightening for the Florida peninsula, wirh a 977 mb potential Major TC riding right up along the Florida Gulf Coast and heading toward Apalachee Bay moving N/NW. starting late Monday

The run ends at 964 mb landfall just east of Apalachicola in the Big Bend 12Z Wednesday morning. WOW!!!!

This would be devastating if this comes to fruition.

[jlauderdal]

South Florida residents, you have been alerted:

Eric Blake
@EricBlake12
Well, here we go again. Today’s my day to make sure I have everything I need for this system. Much easier to fill up the car soon and get a few fine-tuning supplies rather than wait for the last minute and deal with crowds. #TD13

[NDG]

Looking good this morning, a legit TD this morning.

[SconnieCane]

Looking good this morning, a legit TD this morning.

https://i.imgur.com/pwV2aon.jpg

An hour and a half ago it looked "horrible" according to SFLcane.

[Chemmers]

Does anyone think this might take a similar track to the labour day hurricane, hopefully won’t be anywhere near as strong

[DestinHurricane]

I have a bad gut feeling that this is going to be the one to break the "forcefield".

[Frank P]

Early vis sat loops indicate that 13 looks pretty healthy to me... overall cloud presentation is impressive and quite large too for a depression

[Nimbus]

Hope that little southwestern vort doesn't decide to split off and develop we have enough to track out there already. Models still showing a trapping ridge yuck.

[SFLcane]

I have a bad gut feeling that this is going to be the one to break the "forcefield".

Yep..

[Shell Mound]

I have a bad gut feeling that this is going to be the one to break the "forcefield".

If the latest modular trends (06Z GEFS, including parallel) are sustained through the end of tomorrow, I will definitely revise my preliminary expectations and call for a very powerful Category-4+ threat to South Florida. Now that the GFS suite accurately depicts current organisational trends and shows a much stronger TD Thirteen through the entire range, its trend toward a stronger ridge and more westerly track in tandem with a stronger system is definitely noteworthy and should not be discounted, especially if it is sustained through tomorrow and the EC suite also caves. The HRWF/HMON runs were the early warning shots.

[Aric Dunn]

Well now that we have a established system, things should go much more smoothly with the models especially after today's recon data gets ingested.

and luckily the overall forecast is pretty straightforward as well.. the only real issue will be land interaction and if it avoids it or not. so let the wobble watching commence.